package com.viz.tools.code;

/**
 * 　　* JavaScript escape/unescape 编码的 Java 实现
 * <p/>
 * 　　* author jackyz
 * <p/>
 * 　　* keep this copyright info while using this method by free
 * <p/>
 */

public class Escape {

    private final static String[] hex = {

            "00", "01", "02", "03", "04", "05", "06", "07", "08", "09", "0A", "0B", "0C", "0D", "0E", "0F",

            "10", "11", "12", "13", "14", "15", "16", "17", "18", "19", "1A", "1B", "1C", "1D", "1E", "1F",

            "20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "2A", "2B", "2C", "2D", "2E", "2F",

            "30", "31", "32", "33", "34", "35", "36", "37", "38", "39", "3A", "3B", "3C", "3D", "3E", "3F",

            "40", "41", "42", "43", "44", "45", "46", "47", "48", "49", "4A", "4B", "4C", "4D", "4E", "4F",

            "50", "51", "52", "53", "54", "55", "56", "57", "58", "59", "5A", "5B", "5C", "5D", "5E", "5F",

            "60", "61", "62", "63", "64", "65", "66", "67", "68", "69", "6A", "6B", "6C", "6D", "6E", "6F",

            "70", "71", "72", "73", "74", "75", "76", "77", "78", "79", "7A", "7B", "7C", "7D", "7E", "7F",

            "80", "81", "82", "83", "84", "85", "86", "87", "88", "89", "8A", "8B", "8C", "8D", "8E", "8F",

            "90", "91", "92", "93", "94", "95", "96", "97", "98", "99", "9A", "9B", "9C", "9D", "9E", "9F",

            "A0", "A1", "A2", "A3", "A4", "A5", "A6", "A7", "A8", "A9", "AA", "AB", "AC", "AD", "AE", "AF",
            "B0", "B1", "B2", "B3", "B4", "B5", "B6", "B7", "B8", "B9", "BA", "BB", "BC", "BD", "BE", "BF",
            "C0", "C1", "C2", "C3", "C4", "C5", "C6", "C7", "C8", "C9", "CA", "CB", "CC", "CD", "CE", "CF",
            "D0", "D1", "D2", "D3", "D4", "D5", "D6", "D7", "D8", "D9", "DA", "DB", "DC", "DD", "DE", "DF",
            "E0", "E1", "E2", "E3", "E4", "E5", "E6", "E7", "E8", "E9", "EA", "EB", "EC", "ED", "EE", "EF",
            "F0", "F1", "F2", "F3", "F4", "F5", "F6", "F7", "F8", "F9", "FA", "FB", "FC", "FD", "FE", "FF"
    };

    private final static byte[] val = {0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,

            0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F

    };

    public static String escape(String s) {

        StringBuffer sbuf = new StringBuffer();

        int len = s.length();

        for (int i = 0; i < len; i++) {

            int ch = s.charAt(i);

            if (ch == ' ') { // space : map to '+'

                sbuf.append('+');

            } else if ('A' <= ch && ch <= 'Z') { // 'A'..'Z' : as it was

                sbuf.append((char) ch);

            } else if ('a' <= ch && ch <= 'z') { // 'a'..'z' : as it was

                sbuf.append((char) ch);

            } else if ('0' <= ch && ch <= '9') { // '0'..'9' : as it was

                sbuf.append((char) ch);

            } else if (ch == '-' || ch == '_' // unreserved : as it was

                    || ch == '.' || ch == '!'

                    || ch == '~' || ch == '*'

                    || ch == '/' || ch == '('

                    || ch == ')') {

                sbuf.append((char) ch);

            } else if (ch <= 0x007F) { // other ASCII : map to %XX

                sbuf.append('%');

                sbuf.append(hex[ch]);

            } else { // unicode : map to %uXXXX

                sbuf.append('%');

                sbuf.append('u');

                sbuf.append(hex[(ch >>> 8)]);

                sbuf.append(hex[(0x00FF & ch)]);

            }

        }

        return sbuf.toString();

    }

    public static String unescape(String s) {

        StringBuffer sbuf = new StringBuffer();

        int i = 0;

        int len = s.length();

        while (i < len) {

            int ch = s.charAt(i);

            if (ch == '+') { // + : map to ' '

                sbuf.append(' ');

            } else if ('A' <= ch && ch <= 'Z') { // 'A'..'Z' : as it was

                sbuf.append((char) ch);

            } else if ('a' <= ch && ch <= 'z') { // 'a'..'z' : as it was

                sbuf.append((char) ch);

            } else if ('0' <= ch && ch <= '9') { // '0'..'9' : as it was

                sbuf.append((char) ch);

            } else if (ch == '-' || ch == '_' // unreserved : as it was

                    || ch == '.' || ch == '!'

                    || ch == '~' || ch == '*'

                    || ch == '/' || ch == '('

                    || ch == ')') {

                sbuf.append((char) ch);

            } else if (ch == '%') {

                int cint = 0;

                if ('u' != s.charAt(i + 1)) { // %XX : map to ascii(XX)

                    cint = (cint << 4) | val[s.charAt(i + 1)];

                    cint = (cint << 4) | val[s.charAt(i + 2)];

                    i += 2;

                } else { // %uXXXX : map to unicode(XXXX)

                    cint = (cint << 4) | val[s.charAt(i + 2)];

                    cint = (cint << 4) | val[s.charAt(i + 3)];

                    cint = (cint << 4) | val[s.charAt(i + 4)];

                    cint = (cint << 4) | val[s.charAt(i + 5)];

                    i += 5;

                }

                sbuf.append((char) cint);

            }

            i++;

        }

        return sbuf.toString();

    }

//    public static void main(String[] args) {
//
//        String stest = "黄修群1234 abcd[]()<+>,.~//";
//
//        System.out.println(stest);
//
//        System.out.println(escape(stest));
//
//        System.out.println(unescape(escape(stest)));
//
//    }

}
